Method of duplicating



A. J. LEVENHAGEN ETAL June 20, 1944.

METHOD OF DUPLICATING Filed April 25, 1942 5 Sheets-Sheet l BY CUz'ZZL'arn J C/zampwn- June 20, 1944. A. J. LEVENHAGEN EI'AL 2,351,863

METHOD OF DUPLICATING Filed April 25, 1942 I 5 Sheets-Sheet z I June 2 1944- A. J. LEVENHAGEN ETAL 2,351,353

METHOD OF 'DUPLICATING v Filed April 25, 1942 5 Sheets-Sheet s BY Cl/illiazn JC/zanzpion- June 20, 1944. A. J. LEVENHAGEN ETAL 2,351,853

METHOD 0F DUPLICATING Filed April 25, 1942 s Sheets-Sheet s INVEINTORS- By 501' ZZz'am Clzampwn.

alzZ, 541L140",

Patented June 20, 1944 METHOD OF DUPLICATING Arthur J. Levenhagen and William J. Champion, Chicago, Ill., assignors to Ditto, Incorporated, Chicago, IlL, a corporation of West Virginia Application April 25, 1942, Serial No. 440,494

8 Claims.

This invention relates to duplicating by the liquidprocess method and particularly to the method of applying a film of solvent to the inked face of the master sheet and to a structure by which the method can well be worked out. It is the principal object of the invention to provide an improved arrangement of parts by which a thin film of solvent may be applied effectively to the inked face of the master sheet so as to soften the ink very slightly for the production of a copy but so as to prevent the master sheet from bein moistened excessively or discolored or smeared. To this end, it is one of the objects of the invention to provide for a thorough cleaning of the roller or other applicator by which the solvent is spread on the face of the master sheet so that the film of solvent is applied at all times to a clean surface portion of the applicator so as to enable the solvent to be spread evenly and thinly and so that the applicator and the master sheet are protected from becoming sloppy and that the master sheet and the ink thereon are protected from becoming saturated and soggy at spots as would be likely to result if ink were permitted to collect and pile up gradually on the face of the applicator.

It is another object of the invention to provide for the accomplishment of the several objects by the use of a structure which is simple so as to be readily produced and so as to be capable of standing up well during long continued periods of use. It is another object of the invention to provide a structure of this type in connection with a drum by which the master sheet is carried around, with the impression taking place at the bottom face portion of the drum on the top face of a copy sheet, and with the arrangement such that none of the solvent or other liquid employed is likely under any circumstances to leak or to be carried by capillary attraction or otherwise abnormally through the liquid handling and shielding parts of the machine so as to come into contact with a copy sheet and to be transferred therefrom to the face of the master sheet.

In one form of arrangement for carrying out the objects of the invention, a thin and readily absorbent masking sheet is provided over the inked face of the master sheet so that the film of solvent is applied through the masking sheet. For operation in this manner, requiring that there be a liberal supply of solvent, a pick-up roller is employed in lieu of a wick for feeding the solvent to the applicator roller, a third roller also being employed preferably between the pick-up roller and the applicator roller.

It is another object of the invention to improve mechanisms and methods of this type in sundry details hereinafter set forth. The preferred means by which the several objects of the invention are attained is illustrated in the accompanying drawings, in which- Fig. 1 is a longitudinal vertical sectional view through a duplicating machine comprising the invention, being substantially a section taken at the line l| of Fig. 3;

Fig. 2 is a horizontal sectional view taken substantially at the line 2-2 of Fig. 1;

Fig. 3 is a transverse vertical sectiona1 view taken substantially at the line 3-3 of Fig. 1 and with certain parts omitted for clearness of illustration;

Fig. 4 is a longitudinal vertical sectional view showing a portion of the structure of Fig. 1 but upon an enlarged scale, being taken substantially at the line 4--4 of Fig. 3;

Fig. 5 is a view similar to Fig. 4 but showing a modified construction arranged for a, slightly changed operation; and

Fig, 6 is a face view of the drum of Fig. 5 as seen from the left in said figure on a reduced scale, with a portion of the masking sheet broken away.

Referring now to Figs. 1 to 4 of the drawings, in which corresponding parts are indicated by the same reference characters, [0 and II indicate standards at opposite sides of a liquid process duplicating machine connected by transversely positioned crossbars l2 and I3. Between the standards Ill and H, a duplicating drum I4 is rotatably supported by means of a heavy shaft i5, such drum being provided with means comprising grippers l6 of any approved type for holding a master sheet l'l removably in position thereon, the master sheet ll being in the form of a sheet of paper provided on its outer face with a design formed in reverse from hectograph ink, as is well understood in connection with machines of this type. Means is provided for rotating the drum l4 continuously during the operation of the machine, comprising a gear I8 fixedly mounted on the shaft l5 and meshing with a smaller gear 19 rotatably mounted on the standard ll so as to be driven by a crank 20, as is clearly shown in Fig. 2.

Below the drum [4, an impression roller 2| is rotatably mounted in position for pressing a copy sheet fed from the left in Fig. 1 into impression relationship with the master sheet l1, such impression roller 2| being rotatably mounted between two levers 22 pivotally mounted at 23 at opposite sides of the machine. At their lower ends, the levers 22 are provided with pins 24 adjustably mounted thereon in position to engage cams 25 rotatably mounted by means of a shaft 26 extending across the machine. The arrangement is such that by rotary movement of the cams through the medium of the shaft the arms 22 are swung about the axis at 23 for moving the impression roller 2| toward and from the drum for controlling the degree of pressure between the drum and the roller.

At a short distance to the rear of the impression roller 2|, two copy sheet forwarding rollers 21 and 28 are rotatably mounted in position, the roller 21 being secured by means of a shaft 29 mounted in the standards l and II, and the roller 28 being supported by means of a shaft 3!) bearing upon arms 3| pivotally mounted on said standards. As is best shown in Fig. 1, the arms 3| extend backwardly toward the left a short distance so as to provide adjustable connections for springs 32 therewith, such springs having their lower ends connected with said standards so as to press the roller 28 yieldingly against the roller 21. The means for driving the rollers 21 and 28 at substantially the same surface speed as that of the drum l4 comprises a pinion 33 fixedly connected with the roller 21, such pinion 33 meshing with an idler pinion 34, which in turn meshes with a large gear 35 rotatably mounted on the shaft l5.

Means is provided for driving the gear 35 intermittently from the drum 14 or from the means by which the drum is rotated, such intermittent driving means being of the type shown and described by prior patent to Neal No. 2,275,455, of March 10, 1942. This means comprises a cam 36 fixedly mounted on the shaft 15 and provided with a pawl 31 pivotally mounted on the inner face of the cam in position for engagement with a ratchet wheel 38 fixedly mounted on the outer face of the gear 35. The arrangement is such that when the pawl 31 is in engagement with the ratchet wheel 33 the gear 35 rotates with the drum. so as to drive the roller 21 at substantially the same surface speed as that of the drum.

For obtaining an intermittent driving of the roller 21 while the drum I4 is driven continuously, a cam 39 is provided in stationary position on the framework of the machine so as to engage a roller 40 carried by the pawl 31. The arrangement is such that upon each revolution of the drum I4 the roller 40 is moved inwardly so as to disengage the pawl 31 momentarily from one tooth of the ratchet wheel 38 for permitting the gear 35 to be brought to rest while the cam continues to rotate. As soon as the roller 40 passes the cam 39, the pawl 31 is again brought into operative position so as to engage the next succeeding tooth of the ratchet wheel 38 for causing renewed rotation of the gear 35. Means is also provided for stopping the rotation of the gear 35 when the pawl 31 is moved out of operative driving position. This means comprises a series of pins 4| fixedly mounted on the outer face of the gear 35 in circumferentially spaced relation to each other thereabout and arranged in such position that one of the pins is engaged by a notched arm or latch 42 so as to hold the gear from rotary movement when such arm 42 is permitted to move inwardly, such arm or latch 42 being pivotally mounted upon a bracket 42a upon which the cam 39 is mounted. As is shown in Fig. l, the arm 42 is normally held out of operative latching position by means of a roller 43 on the arm engaging the edge of the cam 35, such cam having a low spot at 44 for permitting the arm 42 to move into position for engaging one of the pins 4i for a short period at each revolution of the drum so as to hold the gear 35 and the roller 21 stationary during such period. The parts are so proportioned and arranged that a copy sheet fed into the bite of the forwarding rollers 21 and 28 during the period when the rollers are at rest is moved forwardly by such rollers upon the resumption of their rotary movement so as to have the desired registration with the master sheet on the drum.

For holding a pile 45 of copy sheets in position to be fed one at a time into the bite of the forwarding rollers 21 and 28 and for directing the sheets accurately into position between the rollers, a table 48 of any approved type is provided to the rear of the forwarding rollers, an obliquely disposed guiding member 41 in the form of a plate being provided above the path of the copy sheets for assisting in the feed of the sheets into position. A tray 48 is also mounted in position a short distance ahead of the impression roller 2! for receiving the copy sheets from the drum after the several impression operations.

The improved means for applying a film of solvent on the inked face of the master sheet I1 is best shown in Figs. 3 and 4. Two heavy plates 49 and 50 are pivotally mounted in position opposite to each other at opposite sides of the machine, being pivotally supported by means of pins 5| extending into suitable openings in lugs 52 positioned on the inner faces of the standards l0 and II (see Fig. 3). Between the upper end portions of the plates 49 and 50, a roller 53 is rotatably mounted so as to engage the face of the master sheet 11 on the drum, as is best shown in Fig. 4. At their lower ends, the plates 49 and 50 have links 54 pivotally connected thereto, such links extending rearwardly through openings in a crossbar 55 carried by the standards l0 and. I I, such links having nuts 56 secured by means of screw-threads on their rear ends so as to press the roller 53 adjustably toward the drum 14. A gear 51 fixedly mounted on the roller 53 meshes with a large gear 59 mounted so as to rotate with the drum i4, the parts being accurately proportioned for causing the roller to have the same surface speed as that of the master sheet on the drum in its rotation in clockwise direction in Fig. 4.

Means is provided for applying a film of solvent to the face of the roller 53, comprising an absorbent pad 59 mounted on a plate 60 so as to bear on the top face of said roller 53, said plate 60 being pivotally mounted in position on the plates 49 and 50 by means of a rock-shaft 6| welded or otherwise rigidly secured thereto, as is best shown in Fig. 4. At opposite end portions, the rock-shaft 61 is provided with downwardly extending arms Gla in rigid position thereon, the lower ends of said arms being connected through springs 62 with the plates 49 and 50 so as to press the pad 59 yieldingly against the roller 53. The pad 59 is adjustably pressed against the plate 80 by means of a cross-positioned plate 63 underneath the pad connected with the plate 60 by means of a series of bolts 64. At its rear end portion, the pad 59 extends downwardly into a supply of solvent 65 in a receptacle 66 positioned on the plates 49 and 50 just to the rear of the roller 53. At the left in Fig. 3, the receptacle 65 is prolonged beyond the plate 49 and is provided with an upwardly open neck portion 61 into which a nipple 88 opens, the upper end of the nipple being in engagement with the neck of a bottle 69 containing a supply of solvent, the arrangement being such that solvent is fed by gravity into the receptacle to a predetermined level therein as controlled by a liquid seal effect and as is well understood in the art. In the arrangement shown, the bottle 69 is supported in position by a bracket 10 carried by the standard ID, as shown in Fig. 4.

With the nuts 56 adjusted for causing the deaccuses sired degree of pressure of the roller 58 against the drum 4, and with a supply of solvent in the receptacle 88, the solvent is carried by capillary attraction through the pad 58 and is applied to the top face of the roller 53 as said roller and the drum l4 rotate in operative engagement with each other, the amount of the solvent applied being controlled by the adiustment of the cross plate 83 toward the top plate 80. This film of solvent is in turn applied to the inked face of the master sheet by the engagement of t e moistened roller 53 directly therewith. the film of solvent causin a slight softening of the ink on the master sheet so as to bring about the formation of a copy on each of the several successive copy sheets pressed by the impression roller 2| against the master sheet.

For preventing any of the softened ink on the master sheet from building up on the roller 88 so as to cause the roller to become sloppy or so as to produce a smudging effect on the master. a film of ink neutralizing agent is applied to the face of the roller below the point at whlchthe roller engages the master sheet. The means for effecting this result comprises an absorbent pad 1| supported by a cross-positioned plate 12 so as to press on the bottom face of t e roller 53, the plate 12 being pivotally mounted in position by means of end flanges or arms 13. the upper ends of which are connected throu h the medium of coiled springs 14 with the wall of a receptacle I so as t ress the p d yieldin ly against the roller. The springs 14 are connected with the wall of the receptacle by means of adjustable eye-bolts 18 by which the de ree f pressure of the pad against the roller may be controlled. The rear end portion of the pad di s into a supply of ink neutralizing a ent in t e receptacle so as to cause a film of the ink neutralizing agent to be applied to the face of the roller continuously during the o eration of t e machine. The pad H is preferab y press d into tight engagement with the plate 12 by means o a cross plate 72a posit oned above the pad and connected adjustably therewith by means of v bolts 12b.

The invention is not to be limited to t e use of any particular type of ink neutralizing agent. except so far as the same may be specifically claimed. Good results have been attained in connection with hectograph ink by the use of a solution of ethylene d amine. or by the use oi a 10% solution of hydrochloric acid. or by the use of a 2% solution of sodium hypochlorite.

By the use of an ink neutralizing agent on the roller 53 as above described. any tendency for the ink to build up on the roller from the master sheet is effectively prevented, and the solvent is applied continuously upon a thoroughly cleaned portion of the applicator roller. In this way, the master sheet is kept comparatively clean and dry so as to make possible the production of sharp copies. For insuring that the roller 58 may be cleaned thoroughly, a wiper I1 is prefera-bly employed at the upwardly moving face portion of the roller 53, such wiper being mounted on a cross plate 18 so as to press on the roller, the wiper being adjustably mounted on the plate 18 by means of a top pressure plate 19 adjustably secured in position by means of machine screws 80. In the preferred form of mechanism, the roller 53 is made of steel or other suitable metal with its surface as smooth as possible so as to prevent solvent from penetrating the face of the roller or from finding lodgement in any indenta- OUUHJII UL tions in the face of the roller. With the roller 58 highly smooth and with the film of solvent thereon of even thickness over the surface, the solvent is applied to the ink of the master sheet evenly and without any excess of solvent at any point. The result is that the outer face portions only of the ink bodies of the master sheet are moistened so as to prevent the solvent from soaking into the bodies of the ink while at the same time softening the outer faces sufficiently for causing the formation of a sharp copy on the copy sheet when pressed firmly against the master sheet by the impression roller.

Referring now to Figs. 5 and 6. which show a modified form of the moistening mechanism. the parts are indicated by the same reference characters as above specified so far as the parts are the same as those making u the form of mechanism as shown in Fig. 1. In the modified construction. an applicator roller 8| is employed substantially similar in its form and in the mounting means therefor except that it is of smaller size than the roller 53. The roller 8| is driven by means of a pinion 82 meshing with the large gear 58 so as to drive the roller 8| continuously at the same surface speed as that of the master sheet I1 carried by the drum l4. The arrangement with respect to the master sheet is different in Figs. 5 and 6 from the arrangement shown in Figs. 1 to 4. in that an absorbent masking sheet 83 is employed in connection with the master sheet ll, the two sheets I! and 83 being secured in position together by means of the grippers IS, with the absorbent masking sheet 83 on the outside of the master sheet next to the inked face thereof.

Modified means is provided for applying solvent to the face of the applicator roller 8| so as to provide a slightly heavier film of solvent thereto. The means for applying the solvent to the roller 8| comprises a roller 84 rotatably mounted above the roller 8| in pressure relationship thereto, together with a roller 85 engaging the downwardly moving face of the roller 84. The roller 84 is mounted so as to be adjustable obliquely downwardly and outwardly for varying its pressure relationship with respect to the rollers 8| and 85. A coiled spring 88 is connected with the roller 84 at each end thereof so as to press the roller yieldingly into its pressure relationship with both of the cooperating rollers. The means for applying solvent to the three rollers 8|, 84 and 85 comprises a receptacle 81 containing a supply of solvent 88 into which the lower portion of the roller 85 dips so as to pick up a supply of solvent for application first to the roller 84 and for application from that roller to the roller 8|. The thickness of the film of solvent thus applied is controlled by the pressure between the rollers 84 and 85 as regulated by the springs 88 which are made adjustable for controlling their eifective pressure. End plates 89 of any approved type are employed at the ends of the rollers 84 and 85 for preventing the solvent from running lengthwise off the rollers out of the trough provided by said two rollers, as is well understood in the art. The receptacle 8'! is provided at one end with an upwardly open neck portion 88 into which a nipple 88 extends for carrying solvent from a bottle 88 to the receptacle 81 as is above described in connection with the structure of Fig. 3.

The means for applying ink neutralizing agent upon the bottom face portion of the roller 8| is very similar to that above described in connection with the applicator roller 53. This means comprises an absorbent pad 9| mounted between plates 82 and 93 which are pressed together by means of bolts 94, the pressure of the pad against the roller 8| being controlled by means of arms 95 connected with the plate 92 and pressed yieldingly in counterclockwise direction in Fig. 5 by means of springs 96 connected to the mounting plates 49 and 50. The lower end portion of the absorbent pad 9| extends downwardly into a supply 91 of ink neutralizing agent contained in a receptacle 98. An absorbent wiper pad 99 is provided in position to engage the upwardly moving face portion of the applicator roller 8|, such pad being mounted in position by means of plates I and I (ll secured together at opposite faces of the pad by means of machine screws I02.

As is stated above, the applicator roller 8| is generally similar to the roller 53, being formed with a metal facing which is made very smooth and even on its outer face. The roller 84 is preferably made of Neoprene or rubber of about 50 to 55 Shore hardness. The roller 85 is made of comparatively harder material such as Roulene or possibly of metal. Each of the rollers 8|, 84 and 85 has an outer surface impervious to the solvent 88.

By the use of the mechanism as shown in Figs. and 6, the film of solvent is applied to the inked face of the master sheet I! through the absorbent masking sheet 83. With the masking sheet 83 in position over the master sheet, the ink of the master sheet is protected from becoming overmoistened so as to become sloppy or smudged or discolored, the ink characters being thus maintained intact with sharp outlines so as to produce clean-cut copies on the copy sheets pressed against the masking sheet by the impression roller 2|.

While the form and arrangement as shown and described are preferred, the invention is not to be limited thereto except as the claims may be so limited, it being understood that changes in the arrangement and the method might well be made twithout departing from the spirit of the invenion.

What is claimed is:

l. The method of duplicating which comprises the step of applying solvent by means of a moving applicator to the inked face of a master sheet, and the step of applying an ink neutralizing agent to the face portion of the applicator moving from its point of contact with the master sheet to the point of application of solvent thereto.

2. The method of duplicating which comprises applying a thin film of solvent upon the face of a moving applicator, applying a thin film of ink neutralizing agent on the face of said applicator at a point in spaced relation to the point at which said solvent is applied, and bringing the inked face of a master sheet into engagement with the face portion of th applicator between the points of application of solvent and ink neutralizing agent thereto for applying the solvent to the ink of the master sheet.

3. The method of duplicating which comprises applying a thin film of solvent upon the face of a revolving applicator, applying a thin film of ink neutralizing agent on the face of the applicator at a point in spaced relation to the point at which said solvent is applied, bringing the inked face of a master sheet into engagement with the face portion of the applicator at one side thereof between the points of application of solvent and ink neutralizing agent thereto so as to apply the solvent to the ink of the master sheet, and wiping the neutralizing agent from the applicator at the opposite side thereof ahead of the application of the solvent thereto.

4. The method of duplicating which comprises the step of applying solvent to the inked face of a master sheet through an absorbent masking sheet.

5. The method of duplicating which comprises the step of applying solvent through an absorbent masking sheet to the inked face of a master sheet by means of a moving applicator, and the step of applying an ink neutralizing agent to the face portion of the applicator moving from its point of contact with the master sheet to the point of application of solvent thereto.

6. A method of duplicating which comprises providing a master sheet with a mirror script image in ink of the matter to be copied and repeatedly carrying out the following steps, spreading a thin film of a solvent for said ink upon an applicator, bringing the inked part of the master sheet and the solvent in said film together whereby to dissolve a portion of the ink, then pressing a copy sheet against the inked part of the master sheet to produce a copy, and removing from the applicator the ink transferred thereto in the act of bringing the solvent thereon and the inked part of the master sheet together, whereby to produce a plurality of copies while limiting the spread of the ink over the master through its solution on the applicator.

7. A method of duplicating which comprises providing a master sheet with a mirror script image in ink of the matter to be copied and repeatedly carrying out the following steps, spreading a thin film of a solvent for said ink upon an applicator, bringing the inked part of the master sheet and the solvent in said film together whereby to dissolve a portion of the ink, then pressing a copy sheet against the inked part of the master sheet to produce a copy, and wiping the applicator, thereby substantially removing the ink transferred thereto in the act of bringing the solvent thereon and the inked part of the master sheet together, whereby to produce a plurality of copies while limiting the spread of the ink over the master through its solution on the applicator.

8. A method of duplicating which comprises providing a master sheet with a mirror script image in ink of the matter to be copied and repeatedly carrying out the following steps. spreading a thin film of a solvent for said ink upon an applicator, bringing the inked part of the master sheet and the solvent in said film together whereby to dissolve a portion of the ink, then pressing a copy sheet against the inked part of the master sheet to produce a copy, and thereafter cleansing the applicator by spreading an ink neutralizer thereon and then wiping the surface to remove the ink transferred thereto in the act of bringing the solvent thereon and the inked part of the master sheet together, whereby to produce a plurality of copies while limiting the spread of the ink over the master through its solution on the applicator.

ARTHUR J. LEVENHAGEN. WILLIAM J. CHAMPION. 

